a modified non coherent pn code acquisition scheme rethnakaran p ubinetics e-mail:...
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A Modified Non Coherent PN Code Acquisition Scheme
Rethnakaran P
UbiNetics
E-Mail: [email protected], [email protected]
Joint work with
P.K.Venkataraghavan PK (Synopsys Inc) and
Tapan Ray (Wipro Technologies)
© UbiNetics 2004 CONFIDENTIAL
Agenda
• Acquisition Problem
• Existing solutions
• Modified Non-coherent Detection scheme
• Performance Analytical, Simulation results
• Summary
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DSSS System (Transmitter)
• Transmit Signal
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DSSS System (Receiver)
• Received Signal
• Down Converted I-Q
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Acquisition Problem
• Identify (Detect) the transmitted PN code (Code Phase)
from the received (I and Q) signals,
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System Model
• Receiver Structure
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Non Coherent Detection Scheme
• Non Coherent Detector Structure
• Why Non Coherent?Unknown Random PhaseData modulation yet to be removed
• PenaltyCompared to Coherent scheme
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Modified Non Coherent Scheme
• DNC Structure
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System Model (Continued)
• Post Detection IntegrationNo Post Detection (L=1)
• Matched Filter Based ReceiverPN Sequence used
• AWGNNo Fading
• DSSS/BPSK
• Performance Criteria – ROCProbability of Detection Vs Probability of False Alarm
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Analytical Results (ROC)
• False Alarm Probability
• Probability of Detection
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Performance (NC Versus DNC)
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DNC Advantage (Over NC)
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Simulation Results
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Summary
• New Structure Proposed
• Analytical Expressions (ROC) Derived
• 2dB SNR Advantage Over Conventional Non Coherent Scheme
• Supported by System Level Simulations
© UbiNetics 2004 CONFIDENTIAL
Q&A
Thank YouRethnakaran P
UbiNetics
E-Mail: [email protected], [email protected]
http://ratnu.tripod.com
http://www.ubinetics.com